Type-writing machine.



Patented Dec. 30, I902.

A. w. CASH} TYPE WBITING'MACHINE.

A umiun filed Sept. 1, laa.)

(No Model.)

Witzwases:

ms Nbnms PETERS no. morozumo. wlsnlmmm D. n.

UNITED STATES PATENT OFFICE.

ARTHUR W. CASH, OF HARTFORD, CONNECTICUT, ASSIGNOR, BY MESNE AS- SIGNMENTS, TO THE ELLIOTT & HATCH BOOK TYPEWRITER COMPANY,

OF NEW YORK, N. Y., A CORPORATION.

'TYPE-WRITING MACHINE.

SPECIFICATION forming part of Letters Patent No. 717,347, dated December 30, 1902.

Application filed September 1, 1886 Serial lilo. 212,359- (No model.)

To all whom, it may concern.-

Be it known that I, ARTHUR W. CAsH, of Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements Pertaining to Type Writing Machines, of which the following is a full, clear and exact description, whereby any one skilled in the art can make and use the same.

My within-described invention relates to the detent that regulates the step-by-step progress of the carriage in such machines.

The object of my improvement is to provide adetent the pawls of which are freed so readily from engagement with the toothrack as to greatly decrease the power required to operate the keys; and a further object of my improvement is to provide a device of this kind in which thepawls or teeth of the detent are freed so readily from engagement with the teeth of the carriage-rack as to enable the latter to be quickly released from said teeth on the carriage-rack, and thus provide a quicker movement of the carriage than in prior machines.

To this end my invention consists in a de tent device that has the engaging-surface of the pawl or of the retainingteeth of the rack beveled or formed at an angle with the plane of motion of the parts toward or from each other and in details of the device as more particularly hereinafter described, and pointed out in the claims. 4

Referring to the drawings, Figure 1 shows 3 5 in plan view a part of a detentlever, a toothrack, and the detentpawls adapted to be used in one form of type-writing machine. Fig. 2 is a detail view in cross-section of these parts on plane denoted by line a; a; of Fig. 1. Fig. 3 is a detail View, in horizontal section, on an enlarged scale, through the detentpawls, illustrating the peculiar feature of my invention. Fig. dis adiagram view, also on enlarged scale, further illustrating the oper- 5 ation of the device. 7

In the accompanying drawings the device shown is one that is particularly applicable to the form of machine shown and described in application for United States Letters Patout Serial No. 200,107, on which issued Patent No. 372,516, dated November 1, 1887, although the points of invention may evidently be em- ,and such embodiments of my improvement in sirable along the detent-lever. bears a fixed detent-tooth or pawl c and a 65 bodied in other forms making the improvement applicable to other classes of machines,

or adaptation to other forms of machines than herein shown is contemplated by me.

In the drawings, the letter a deno es the vibratory cross-bar of the detent-lever of a type-writing machine; 1), the detent-block, having a socket b on the under side and provided with clamp-screws b or like means for securing the detent-block at any point de This block movable tooth or pawl d, the latter being borne on the end of a spring-bar d, that has the usual limited movement toward and from the fixed tooth in the direction in which the paper-carriage travels, the spring d holding the bar in its normal position out of the line of the face of the fixed tooth.

The letter e denotes a rack having teeth 6' and secured to the paper-carriage in position to be moved therewith in the usual manner lengthwise across the detent-teeth c and (1. These teeth 0 d by the swinging or rocking movement of the bar a, to which they are at tached, are thrown inand out of engagement with the teeth of the rack-bar e.

In the operation of the detent device the cross movement of bar a, that slides the fixed detent-tooth 0 out of engagement with a tooth e on the rack e,slides the movable tooth (2 into engagement, as in Fig. 4, with a tooth on the rack, which latter as soon as it is released from the hold of the fixed tooth 0 moves forward, as usual, under the influence of the carriage-impelling spring, carrying the movable tooth into a position in line with thefixed tooth c, as shown in Fig. 3. The return movement of the detent-lever and rock-bar a, to which the detent is secured, releases the movable tooth d from the hold of the rack, the fixed tooth c holding the latter against movement, while the movable tooth d, under the impulse of the spring, is swung backward in position to engage another tooth on the rack when the oscillation of the rock-bar or detentlever is repeated.

In order to facilitate'the sliding of the surfaces of the teeth of the rack and of the detent teeth or pawls upon each other, I provide the holding-faces c and d of the respecone over the other.

tive teeth with a slope or bevel toward the edge last in contact with the teeth of the rack in the releasing movement of these detentteeth.

In the form of my improvement shown in the drawings the edge of a tooth on the rack or equivalent member adapted to be borne on a moving carriage rests on the sloping face of the detent-teeth, so that when the detent operates to release the rack, as by a sidewise movement of one of the interengaging parts, the forward feeding movement of the carriage begins immediately. The advantages of this construction are a gain in the writing speed of the machine and a saving in the power required to operate the keys.

A person skilled in the art of using a typewriting machine attains such speed in striking the keys in quick succession that with the old form of escapement, in which the rackteeth and detent-teeth are provided with engaging holding-surfaces arranged substantially at right angles to the movement of the carriage,succeeding characters may be struck This is due to the slight delay in the forward movement of the carriage on release,owing to the fact that the carriagespring has to overcome the inertia of the carriage. It has been found by experiment that when the edge of a tooth on the rack rests on the inclined surface of a detent-tooth the release is practicallyinstantaneous,and, in fact, so prompt is the action that the fastest writer is unable tostrikeone character-over the other. The speed and ease of writing with a machine in which my improvement is embodied are due to the contact of the edge of the teeth on the forward moving member with the sloping surface of the detent-teeth.

It is obvious that the precise angle of slope of the inclined surface of the teeth depends on the form and style of machine, the character of the escapement, and also on the weight of the carriage, strength of carriage feed-spring, and form of the type-operating levers. Such modifications as will enable my improvement to be adapted to the various forms of type-writing machines are obviously within the knowledge of a person skilled in the making of such machines, and such changes in degree of slope, length of the same, or special arrangement to meet changed conditions in different machines are clearly within the scope of my invention and are contemplated by me.

The operation of the machine is as follows: When used in an ordinary escapement with a tooth of the rack normally resting on the movable tooth d, the tooth of the rack will lie against the beveled surface of said tooth, the latter being at the forward limit of its play, as indicated in the diagram view, Fig. 3, of the drawings. The detent block is now moved in the direction indicated by the arrow in said Fig. 3 bya blow upon a key-lever or space-bar, such blow in ordinary writing being of sufficient force to cause the detent to move quickly, and before the rack overcomes the inertia the detent has been moved to an extent to cause the fixed tooth c to engage the same tooth of the rack as that engaged by the movable tooth d and without forward movement of the rack. The movable tooth 61 now moves backward under the impulse of its spring in position to engage a succeeding tooth on the rack. The tooth on the rack, as shown in the drawings, now rests on the beveled surface of the fixed tooth c, and as pressure on a key-lever or space-bar is released the detent, under the impulse of its spring, is moved in the direction indicated by the arrows in Fig. 4 of the drawings, the rack under the impulse of the carriagespring beginning its forward feeding movement at the same instant that the detent begins its movement. The movement of the detent toward the left takes place at the time that the movable tooth d is free to be swung forward, and this, in connection with the detent-sprin g, moves the detent a distance sufficient to cause a tooth on the rack to engage the beveled surface of the movable tooth in the position indicated in Fig. 3 of the drawings. The strength of the detent-spring is sufficient to cause the parts to assume this position, the movable tooth of course having been moved forward to the position indicated in Fig. 3, when the operation is repeated. The beveled surface on the movable tooth (1 allows said tooth to begin its backward movement for engagement with a succeeding tooth on the rack immediately at the commencement of the movement of the detent and insures its reaching the proper position to engage with said succeeding toot-h on the rack on the return movement of the detent. It is obvious that the beveled surface on the movable tooth does not have any effect in aiding the quick forward movement of the rack when the carriage normally rests on the movable tooth.

I claim as my invention- 1. In a type-writer escapement, the combination with a toothed member adapted to be connected with a power-driven carriage, and a detent having teeth adapted to engage those on the toothed member, of an inclined face on an engaging tooth arranged and adapted to release said toothed member and enable it to commence its movement during the disengaging movement of the toothed parts.

2. In a type-writer escapement, in combination with a rack adapted to be secured to a power-driven carriage, and a detent, of an inclined face on the detent arranged and adapted to release the rack and enable it to commence its forward feeding movement.

3. In combination with the toothed rack of the carriage of a type-writing machine, a detent device having a fixed and a movable tooth with their edges adjacent to each other beveled on the sides opposing the forward movement of the carriage, all substantially as described.

4. In combination with the toothed rack e, the cross-bar a of the detent-lever, the detent-block b with the clamp-screws and having a fixed tooth e and a movable tooth d, both teeth having beveled holding-faces on their adjacent edges, all substantially as described.

5. In a type-writing machine, in'combination with a toothed rack e, the rocking bar and the detent-block secured thereto, the fixed and movable detent-teeth attached to said block and having the rounded or beveled en gaging faces, all substantially as described.

6. In a type-writerescapement, the combination with a rackadapted to be secured to a power-driven carriage, and a detent, of an inclined face arranged and adapted to release the rack and enable it to commence its forward feeding movement as soon as pressure on the key-lever is released.

7. In a type-writing machine, in combination with an escapement-rack, a detent having a fixed tooth and a movable tooth, the working surface of said teeth being arranged at an angle to the plane of movement of the rack and adapted to cooperate with the rack so as to enable the forward feeding movement to begin at the commencement of the releasing movement of the detent, all substantially as described.

8. In a type-writer escapement, the combination with a rack adapted to be secured to a power-driven carriage, and a detent, of an inclined face on one of said parts arranged and adapted to release the rack and enable it to commence its forward feeding movement at the commencement of the releasingmovement of the detent, all substantially as described.

9. In a type-writer escapement, the combination with a rack adapted to be secured to a power-driven carriage, and a detent having a tooth adapted to engage the teeth on the rack, of an inclined face on one of said parts on which a tooth'of the opposite part rests whereby feeding movement of the rack is permitted at the commencement of the releasing movement of the detent.

10. In a type-writer escapement, the combination with a rack adapted to be secured to a power-driven carriage, and a detent having a fixed, and a movable tooth adapted to en gage the rack, of an inclined face on a tooth of the detent arranged and adapted to release the rack and enable it to commence its feeding movement during the disengaging movement of the rack and detent.

11. In atype-writerescapement, the combination with a rack adapted to be secured to a power-driven carriage, and a detent having a fixed and a movable tooth adapted to engage the rack, of an inclined face on a tooth nation with a rack adapted tobe secured to a power-driven carriage, and a detent having a fixed and a movable tooth adapted to engage the rack, of an inclined face on a tooth of the detent on which a tooth of the rack rests, whereby feeding movement of the rack is permitted at the commencement of the releasing movement of the detent.

13. In a type-writer escapement, the combination with a rack adapted to be secured to a power-driven carriage, and adetent having a fixed and a movable tooth adapted toengage the rack, of an inclined face on the fixed tooth of the detent arranged and adapted to release the rack and enable it to commence its feeding movement during the disengaging movement of the rack and detent.

14. In a type-writer escapement, the combination with a rack adapted to be secured to a power-driven carriage, and a detent having a fixed and a movable tooth adapted to engage the rack, of an inclined face on the fixed tooth of the detent arranged and adapted to release the rack and enable it to commence its feeding movement at the commencement of the releasing movement of the detent.

15. In a type-writer escapement, the combination with a rack adapted to be secured to a power-driven carriage, and a detent having a fixed and a movable tooth adapted to engage the rack, of an inclined face on the fixed tooth of the detent on which a tooth of the rack rests, whereby feeding movement of the rack is permitted at the commencement of the releasing movement of the detent.

16. In a type-writer escapement, the combi* nation of two elements in one member which alternately engage with the other member, both elements having their edges adjacent to each other provided with inclined faces on the sides opposing the forward movement of the carriage.

17. In a type-writing machine, the combination with a rack, of a normally engaged dog having a beveled face on its side opposing the movement of the carriage, substantially as described.

18. In the escapement of a type-writing machine, the combination with a rack, of a normally disengaged dog having a beveled face on its side opposing the forward move-, ment of the rack.

19. In a type-writer escapement, the combination with an escapement-rack adapted to be secured to a power-driven carriage, a detent having a tooth with a working face arranged at an angle to the plane of movement of the'tooth and adapted to cooperate with therack so as toenable the rack andcarriage to commence their letter-space movement at the commencement of the return movement of the tooth and type.

ARTHUR W. CASH.

Witnesses:

CHAs. L. BURDETT, A. W. SPERRY. 

